48 
rested upon the twigs and not upon the walls of the case. I do not 
think, in any of the previous experiments with larvae, that equal effects 
have been produced in this manner, and one is tempted to inquire 
whether it is possible that the larvae, in earlier and specially sensitive 
stages, did not actually rest upon the black and white walls of the 
case.” 
I confess I am not cognisant of the conclusions at which Mr. 
Merrifield arrived from the above experiments, hut it would seem that 
the evidence goes to show that there must be a power at work besides 
natural selection in bringing about those forms of insect life which so 
closely resemble their immediate environment, as in the above experi¬ 
ment there is a strong tendency to assimilate to environment, without 
the inffuence of heredity entering into the question, which in “ Natural 
Selection ” is an all important factor. 
I will conclude by saying that I hope I have not tired the 
members present by a repetition of facts which, doubtless, many of 
them have heard before, hut of those who have I will ask their 
indulgence. 
AFTER LEPIDOPTERA IN BRITISH GUIANA IN 1901. 
(Read February 18th, 1902, by W. J. KAYE, F.E.S.) 
This is a holiday paper, and must be looked upon as a fill-up, as it 
were, to our programme, for want of sufficient solid matter. I have 
chosen a somewhat wide-embracing title, and 1 suppose I should be 
within the meaning of the Act if 1 began with the vicissitudes of the 
journey on the way to British Guiana, and describe the horrors or 
elysiums of the first three days out. Those who already know them¬ 
selves to be bad sailors would probably never be induced to go so far 
afield, so I shall not be guilty of putting them off if I tell them that 
the sea was just the reverse to the surface of a billiard table, and only 
ten people out of 70 turned up for meals on those three first days. How¬ 
ever, Barbadoes was reached on the twelfth day, and, after transhipping 
there, Georgetown was but another two days’ journey. Georgetown is 
literally below the level of the sea, and in times past, when the drain¬ 
age was not all that it should have been, has suffered terribly from 
epidemics of yellow fever. It is only ‘20 years since a visitation, and 
unless the drainage can still be improved it is dreaded that another 
outbreak may occur. For six days 1 remained in the town, calling on 
various people and gathering what information I could as to collecting 
and localities. This information turned out to he very meagre if 
that, and 1 made up my mind, once and for all, to go my own way, 
at any rate until 1 could interview the curator of the museum, Mr. 
Quelch, who was away in the bush. 
